Project Summary Prenatal alcohol exposure (PAE) is the leading non-genetic cause of intellectual and other brain disabilities. However, fetal alcohol spectrum disorders (FASD), estimated to affect ~2-5% of school-aged children in the US, remain difficult to diagnose and to prevent. Our recent work (PMCID 5102408) identified several circulating microRNAs (miRNAs) in heavy alcohol-consuming pregnant women whose expression levels in the 2nd and 3rd trimester predicted adverse infant outcomes including craniofacial anomalies and neurobehavioral and growth deficits1. Specifically, Analysis of Variance (ANOVA) models identified 11 elevated plasma miRNAs in mothers whose infants were severely affected by alcohol consumption. Using Random Forest Analysis (RFA), we were further able to use a distinct group of miRNAs to classify infants apparently unaffected by ethanol exposure with affected infants as opposed to alcohol unexposed infants. Aside from their diagnostic value, it is unknown if these Maternal circulating miRNAs associated with Adverse Infant Outcomes (M-circmiRNA-aAIO) contribute to the developmental pathologies of FASD. Bioinformatic analysis suggests these circulating miRNAs potentially regulate important hub genes for STAT3 and ephrin signaling pathways, which are in turn known to control cycles of epithelial mesenchymal transition (EMT) crucial for normal embryogenesis and placental and fetal development. Therefore, my overarching hypothesis is that PAE impairs early development by interfering with the endocrine action of circulating maternal miRNAs on both the placenta and fetus. In my research proposal, using both human cell lines and in vivo mouse models, I will test the hypothesis that pathogenic levels of circulating miRNAs mediate effects of ethanol on placenta and fetus and that they control embryo growth and survival by regulating EMT-like behaviors of key placental and fetal cells. The long-term goals of this project will be to develop interventional strategies that exploit the biology of endocrine circulating miRNAs in mitigating negative outcomes due to PAE and other teratogens. My immediate goals will be to define the role of maternal miRNAs, which predict FASD outcomes, on placental and embryo growth and development. Aim 1: Determine the impact of M-circmiRNA-aAIOs on trophoblast growth, survival, migration and invasion under basal and ethanol exposed conditions. Aim 2: Determine the impact of M-circmiRNA-aAIOs on embryonic growth, death, and cellular maturation/differentiation under basal and ethanol exposed conditions. Aim 3: Determine the impact of M-circmiRNA-aAIOs on in vivo fetal development and neonatal outcomes. My studies are expected to uncover novel endocrine and pregnancy related functions of FASD-associated maternal systemic miRNAs and may provide novel therapeutic targets and non-invasive modalities to mitigate effects of PAE. Given its translational potential, this project will further my training as a physician-scientist interested in pursuing both clinical duties and research on early developmental disorders.